6082铝合金热变形的本构模型-中国有色金属学报.PDF

第 18 卷第 10 期 中国有色金属学报 2008 年 10 月 Vol.18 No.10 The Chinese Journal of Nonferrous Metals Oct. 2008 文章编号：1004-0609(2008)10-1769-06 6082 铝合金热变形的本构模型 李雪松，陈 军，张鸿冰 (上海交通大学 国家模具CAD 工程研究中心，上海 200030) 摘 要：利用Gleeble−1500 热模拟机，研究 6082 铝合金在变形温度为 300~500 ℃以及应变速率为0.01~10 /s下高 温单道次压缩过程的热变形流变应力行为。结果表明：6082 铝合金高温单道次压缩下的热变形经历了从应变硬化 阶段过渡到稳态变形阶段的过程，其软化机制主要为动态回复。该合金流变应力的大小受变形温度、应变速率的 强烈影响，它随变形温度升高而降低，随应变速率提高而增大，说明该合金是一个正应变速率敏感的材料。该合 金高温流变应力σ可采用Zener-Hollomon参数的函数来描述，函数表达式中参数A 、α和n 的值分别为 3.97 ×1011 s−1、 0.01 MPa−1、9.16 ；其热变形激活能Q为 143.89 kJ/mol。 关键词：6082 铝合金；热压缩变形；本构模型 中图分类号：TG 146.2 文献标识码：A Constitutive model for hot deformation of 6082 aluminum alloy LI Xue-song, CHEN Jun, ZHANG Hong-bing (National Die Mold CAD Engineering Research Center, Shanghai Jiao Tong University, Shanghai 200030, China) Abstract: The flow stress behavior of 6082 aluminum alloy was studied by single-pass high temperature compression experiment on Gleeble−1500 thermal-mechanical simulator, over a range of temperature of 300−500 ℃ and a range of strain rate of 0.01−10 /s. The results demonstrate that the hot deformation behavior of 6082 aluminum alloy exhibits strain-hardening to a steady-state, and the softening mechanism was mainly controlled by dynamic recovery (DRV). The value of flow stress is significantly affected by deformation temperature and strain rate, which decreases as temperature becomes higher and as strain rate becomes lower, indicating that 6082 aluminum alloy is a positive strain rate sensitive material. The flow stress of this alloy can be represented by Zener-Hollomon parameter function , and values of